Field of the Invention 1
This invention relates to devices used inside buildings into which pets can release excrement, and more particularly to pans having provision for controlling and eliminating odors produced by such excrement.
Description of the Prior Art 2
When pets are to be confined indoors, it is necessary to provide a place in which they can release liquid urine and solid feces. Conventionally, a fairly shallow pan or tray is provided, and the tray is partially filled with granular absorbtive material commonly called "litter". The litter is supposed to absorb the liquid urine and cover the solid fecal matter.
While such litter trays are reasonably effective when freshly cleaned out and filled with fresh litter, they become quite smelly after even a short time after use and hence must be cleaned and refilled quite often. Cleaning is commonly accomplished by emptying the contaminated litter into a paper bag and placing such bag in the household garbage. The pan must then be washed to removed dried excrement which may be clinging to it. After the pan is dried it is partially filled with fresh litter and it again available for the pet's use.
Attempts have been made to control the offensive odor so that the litter pan can be used for a longer period of time between emptying and cleaning operations. Commonly, this is done by mixing a dry material with the litter which is capable of absorbing odors (such as activated charcoal) or reacting with the liquid urine to release odor-masking chemicals. This solution is only partly effective, and the litter trays must still be emptied and cleaned quite often.
other attempts to control the odors have been made which involve placing the litter on a perforated screen in such manner that excess liquid urine not absorbed by the litter will drop downwardly through the screen onto an absorptive layer, such as old newspapers, positioned in the bottom of the tray. These devices are complicated and are difficult to empty and to clean before the next use. Typical of such devices are those found in U.S. Pat. No. 4,308,825 to Josephine W. Stepanian, U.S. Pat. No. 4,469,046 to Patrick Yananton, and U.S. Pat. No. 4,615,300 to John P. McDonough.
The above-listed patents are believed to be relevant to the present invention because they were adduced by a prior art search made by an independent searcher, and a copy of each of the above-listed patents is supplied to the Patent and Trademark Office herewith.
The term "prior art" as used herein or in any statement made by or on behalf of the applicant means only that any document or thing referred to as prior art bears, directly or inferentially, a date which is earlier than the effective date of this application.
No representation nor admission is made that any of the above-listed documents is part of the prior art in any acceptation of that term, or that no more pertinent information exists.